I planted a bed of asparagus in 2012. It takes three years for asparagus to establish—like most things in the garden, the rule of thumb is year one sleep, year two creep, and year three leap. And that’s exactly what happened. In 2015, we had amazing asparagus for three weeks, fresh out of the garden delicious.
According to everything I’ve read, an established asparagus garden lasts about ten years, although I’ve also heard of thirty-year beds still producing. Last year, a very dry year, we had a somewhat sparse crop. This year, a very wet year, was amazing. We ate asparagus for two full months, about every day. In fact, we’re sort of sick of asparagus.
But. The photo shows yellowish grass in the bed. That is nut grass, also known as nut sedge, formal name Cyperus esculentus and one of the most difficult weeds to control. How’d it get there? I’ve never had it in this or any other bed before now.
I suspect that nut grass seeds were a toxic bonus from the bags of compost/manure I bought at one of the Big Box Stores. What I should have done was opened the bags onto a tarp and let them sit for a year, covered in plastic to bake in the sun. Instead, I simply spread the bag contents onto my asparagus bed.
I tried hand weeding and ended up with hand cramps. Nut grass roots are tangled and deep. I tried weeding with a variety of tools, including my favorite Cape Cod Weeder. No dice. The bare spot in the photo is what I was able to weed by hand.
Researching a herbicide compatible with asparagus, I ended up on the University of California Agriculture and Natural Resource site, and actually found an herbicide that might work, called halosulfuron. Very expensive. Too expensive for an eight-year-old asparagus bed when it will cost less than fifty dollars–and three years–to replace it.
Sedge grass spreads like wildfire and I never want to see it anywhere else in my yard. So I’m—probably—sacrificing my asparagus to keep this highly invasive weed from spreading.
We spayed this morning when the wind was practically nil. I’ve checked, some six hours later, and things in the asparagus bed look yellow. Not the ferns, though. The ferns are still green and I still have hope.
Time will tell.